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771.
Abdolkarim Zare Fatemeh Masihpour 《Phosphorus, sulfur, and silicon and the related elements》2016,191(8):1160-1165
A novel Brønsted acidic ionic liquid namely N,N-diethyl-N-sulfoethanamminium hydrogen sulfate ([Et3N-SO3H]HSO4) was synthesized, and characterized using FT-IR, 1H NMR, 13C NMR, and mass data. Then, its catalytic activity was examined for the preparation of triazolo[1,2-a]-indazole-triones and 2H-indazolo[2,1-b]phthalazine-triones by the one-pot multi-component condensation of arylaldehydes with dimedone and 4-phenylurazole/2,3-dihydrophthalazine-1,4-dione under solvent-free conditions. [Et3N-SO3H]HSO4 efficiently promoted the reaction to afford the products in high yields and in short reaction times. 相似文献
772.
This is an investigation of the implications of IPC which remain provable when one weakens intuitionistic logic in various ways. The research is concerned with logics with Kripke models as introduced by G. Corsi in 1987, and others like G. Restall, Do?en, Visser. This leads to conservativity results for IPC with regard to classes of implications in some of these logics. Moreover, similar results are reached for some weaker subintuitionistic systems with neighborhood models introduced by the authors in 2016. In addition, the relationship between two types of neighborhood models introduced in that work is clarified. This clarification leads also to modal companions for weaker logics. 相似文献
773.
Research on Chemical Intermediates - To cater to the requirement of environmental protection, cetyltrimethylammonium bromide (CTAB)-coated Fe3O4@Ag Nanoparticles as a new hybrid magnetic catalyst... 相似文献
774.
Babakhani Dehkordi Parham Razavirad Fatemeh Shahrabadi Abbas 《Transport in Porous Media》2022,145(1):73-101
Transport in Porous Media - To date, most studies about low salinity water flooding (LSWF) have been conducted at the Darcy scale, taking into account mixed-wet conditions, although a limited... 相似文献
775.
Highly efficient synthesized magnetic cobalt ferrite nanoparticles supported on OCMC@Cu (BDC) was utilized in the preparation of biologically active heterocyclic compounds through one-pot three-component reactions between of aldehydes, dimedone, aryl amines/2-naphthol/urea under ultrasonic irradiation. This method has various advantages including excellent yields, little catalyst loading, simple procedure, facile catalyst separation, short reaction times, eco-friendly approach and simple purification. The catalyst was characterized by various spectroscopy methods such as fourier-transform infrared (FT-IR), energy-dispersive X-ray (EDX), scanning electron microscope (SEM), X-ray diffraction (XRD) and N2 adsorption–desorption isotherm (BET). Furthermore, the heterocyclic compounds were characterized by spectral techniques. The nanocomposite was simply separated byusing an external magnet, and it can be recycled several times without significant loss of activity. 相似文献
776.
Hybrid composite based on graphene oxide (GO) and covalent organic framework (COF) [GO/COF] was developed via a simple solvothermal method, at which GO was applied as a platform to load COF based on melamine and terephthaldehyde. The synthesized hybrid nanocomposite was characterized by FT-IR, XRD, EDX and SEM techniques. Morphological analyses carried out by SEM confirm the successful growth of COF over GO. Then, the resultant composite was employed as an amazing and cost-effective catalyst in the condensation of several aldehydes with malononitrile and produced the corresponding coupling products in high yields (up to 84%) at room temperature under solvent-free conditions with an amount of catalyst, 15 mg in a very short reaction time of 10 min. The catalyst could be reused without a noteworthy drop in catalytic activity at least eight times. The use of GO/COF catalyst outcomes under mild reaction conditions in very short reaction time, exceptional catalytic activity, high recyclability and an easy work-up process for the Knoevenagel condensation. 相似文献
777.
A magnetic nanocomposite based on graphene oxide was prepared. Fe3O4 nanoparticles were loaded on graphene oxide sheets and GO-Fe3O4 was covered by aniline-pyrrole copolymer to afford poly(Py-co-Ani)@GO-Fe3O4. This nanocomposite was characterized by Fourier transform infrared spectroscopy, transmission electron microscopy, vibrating sample magnetometry, X-ray diffraction, thermogravimetric analysis, and X-ray photoelectron spectroscopy techniques, and its catalytic activity was evaluated in the multicomponent synthesis of 2′-aminospiro[indeno[1,2-b]quinoxaline-11,4′-[4'H]pyran]-3′-carbonitrile and 2′-aminospiro[indeno-2,4′-[4'H]pyran]-3′-carbonitrile derivatives. This magnetically separable catalyst is heterogeneous noncorrosive, highly efficient, and reusable. 相似文献
778.
One of the most important challenge in recent years is the removal and even better than that the degradation of poisons from environmental systems. Nanostructures due to their interesting properties are very suitable for this purpose. Herein, Cd3OSO4 nanomaterial was synthesized with a simple co precipitation method, characterized and was used, as a visible-light-driven photocatalyst in degradation of diazinon. The experimental conditions were also optimized. The results showed degradation efficiency is about 90%. Moreover, some kinetic studies were performed and showed this system obeys first order kinetics. Photo- oxidation mechanism was investigated in the presence of hole and electron scavengers. This is the first report on the investigation of the photocatalytic properties of Cd3OSO4 nanomaterial. The calculations of band gap of this new photocatalyst (1.85ev) showed its capability for application as a new visible light driven photocatlyst. 相似文献
779.
A novel triazine-phosphanimine polymeric organic support (TPA) was synthesized successfully by a controllable one-pot method using melamine (1,3,5-triazine-2,4,6-triamine) and trichlorophosphane (PCl3). The TPA substrate is a material incorporating P and N atoms which can coordinate with metals as a pincer ligand to stabilize them, providing an efficient heterogeneous support to prepare recyclable transition metal catalyst systems. In this study, TPA was used as support to immobilize iridium nanoparticles in the range of ~8 nm on its surface, resulting in the generation of a novel iridium nanocatalyst system (INP-TPA-POP). This catalyst system was characterized using different microscopic and spectroscopic techniques such as FT-IR, TEM, XPS, XRD, SEM, EDX, elemental analysis, ICP and BET analysis. The INP-TPA-POP nanocatalyst exhibited remarkable activity in reduction of aldehydes to alcohols using formic acids as reducing agent in ethanol as solvent. 相似文献
780.
Fariborz Omidi Monireh Khadem Fatemeh Dehghani Mirghani Seyedsomeah Seyed Jamaleddin Shahtaheri 《Journal of separation science》2020,43(13):2602-2609
In this research, a new ultrasound‐assisted dispersive micro‐solid‐phase extraction method based on N‐doped mesoporous carbon sorbent followed by high‐performance liquid chromatography equipped with diode array detector for trace measurement of 1‐hydroxypyrene as a metabolite of exposure to polycyclic aromatic hydrocarbons was optimized. Herein, the hard template method was used for the preparation of N‐doped mesoporous carbon sorbent. The prepared sorbent was characterized using the Brunauer–Emmett–Teller method, transmission electron microscopy, and elemental analysis. Parameters affecting the extraction of the target metabolite were investigated using the Box–Behnken design method. Considering optimum parameters, the plotted calibration curve for 1‐hydroxypyrene was linearly correlated with the concentration span of 0.1–50 μg/L for urine media. The accuracy of the optimized procedure was examined through the relative recovery tests on the fortified urine specimens. The relative recoveries fell between 95 and 101%. The method detection limit of the proposed procedure was also calculated to be 0.03 μg/L. 相似文献